Add progressive web app companion for cross-platform access

Vite + TypeScript PWA that mirrors the Android app's core features:
- Pre-processed shelter data (build-time UTM33N→WGS84 conversion)
- Leaflet map with shelter markers, user location, and offline tiles
- Canvas compass arrow (ported from DirectionArrowView.kt)
- IndexedDB shelter cache with 7-day staleness check
- Service worker with CacheFirst tiles and precached app shell
- i18n for en, nb, nn (ported from Android strings.xml)
- iOS/Android compass handling with low-pass filter
- Respects user map interaction (no auto-snap on pan/zoom)
- Build revision cache-breaker for reliable SW updates

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pwa/node_modules/jake/jakefile.js

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+let proc = require('child_process');
+
+const PROJECT_DIR = process.cwd();
+process.env.PROJECT_DIR = PROJECT_DIR;
+
+namespace('doc', function () {
+  task('generate', ['doc:clobber'], function () {
+    var cmd = '../node-jsdoc-toolkit/app/run.js -n -r=100 ' +
+        '-t=../node-jsdoc-toolkit/templates/codeview -d=./doc/ ./lib';
+    jake.logger.log('Generating docs ...');
+    jake.exec([cmd], function () {
+      jake.logger.log('Done.');
+      complete();
+    });
+  }, {async: true});
+
+  task('clobber', function () {
+    var cmd = 'rm -fr ./doc/*';
+    jake.exec([cmd], function () {
+      jake.logger.log('Clobbered old docs.');
+      complete();
+    });
+  }, {async: true});
+
+});
+
+desc('Generate docs for Jake');
+task('doc', ['doc:generate']);
+
+npmPublishTask('jake', function () {
+  this.packageFiles.include([
+    'Makefile',
+    'jakefile.js',
+    'README.md',
+    'package.json',
+    'usage.txt',
+    'lib/**',
+    'bin/**',
+    'test/**'
+    ]);
+  this.packageFiles.exclude([
+    'test/tmp'
+  ]);
+});
+
+jake.Task['publish:package'].directory = PROJECT_DIR;
+
+namespace('test', function () {
+
+  let integrationTest = task('integration', async function () {
+    let testArgs = [];
+    if (process.env.filter) {
+      testArgs.push(process.env.filter);
+    }
+    else {
+      testArgs.push('*.js');
+    }
+    let spawned = proc.spawn(`${PROJECT_DIR}/node_modules/.bin/mocha`, testArgs, {
+      stdio: 'inherit'
+    });
+    return new Promise((resolve, reject) => {
+      spawned.on('exit', () => {
+        resolve();
+      });
+    });
+
+  });
+  integrationTest.directory = `${PROJECT_DIR}/test/integration`;
+
+  let integrationClobber = task('integrationClobber', function () {
+    proc.execSync('rm -rf package.json pkg tmp_publish');
+  });
+  integrationClobber.directory = `${PROJECT_DIR}/test/integration`;
+
+  let unitTest = task('unit', async function () {
+    let testArgs = [];
+    if (process.env.filter) {
+      testArgs.push(process.env.filter);
+    }
+    else {
+      testArgs.push('*.js');
+    }
+    let spawned = proc.spawn(`${PROJECT_DIR}/node_modules/.bin/mocha`, testArgs, {
+      stdio: 'inherit'
+    });
+  });
+  unitTest.directory = `${PROJECT_DIR}/test/unit`;
+
+});
+
+desc('Runs all tests');
+task('test', ['test:unit', 'test:integration', 'test:integrationClobber']);
+
+desc('Runs eslint for both lib and test directories');
+task('lint', function (doFix) {
+
+  let cmd = 'eslint --format codeframe "lib/**/*.js" "test/**/*.js"';
+  if (doFix) {
+    cmd += ' --fix';
+  }
+  try {
+    proc.execSync(cmd);
+  }
+  catch (err) {
+    console.log(err.message);
+    console.log(err.stderr.toString());
+    console.log(err.stdout.toString());
+    fail('eslint failed');
+  }
+});
+
+